Updated 8:11 am, Wednesday, August 8, 2012

Nemo Chu (left) sits in an ergonomic chair while Derek P. Collins stands at his workstation at Kissmetrics in San Francisco, which provides ergonomic desks.

Nemo Chu (left) sits in an ergonomic chair while Derek P. Collins stands at his workstation at Kissmetrics in San Francisco, which provides ergonomic desks.

Photo: Sonja Och, The Chronicle

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Eric Fung (foreground) and Charles Liu stand at their workstations at Kissmetrics, which provides desks that ease back pain and improve blood circulation.

Eric Fung (foreground) and Charles Liu stand at their workstations at Kissmetrics, which provides desks that ease back pain and improve blood circulation.

Photo: Sonja Och, The Chronicle

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Charles Liu, product marketer at Kissmetrics, stands on one foot at his workstation. Getting workers on their feet has been found to offer big benefits.

Charles Liu, product marketer at Kissmetrics, stands on one foot at his workstation. Getting workers on their feet has been found to offer big benefits.

Photo: Sonja Och, The Chronicle

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Nemo Chu, director of customer acquisition at the San Francisco analytics company, sits in his ergonomic chair, which is highly adjustable.

Nemo Chu, director of customer acquisition at the San Francisco analytics company, sits in his ergonomic chair, which is highly adjustable.

Photo: Sonja Och, The Chronicle

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Eric Fung, Support Engineer at KISSMetrics, stretches his legs while he is working. A growing number of workplaces are letting their employees use standing desks to alleviate back pain and improve blood circulation. Web analytics company KISSMetrics is one of them in San Francisco, Calif. on Monday, July 30, 2012.

Eric Fung, Support Engineer at KISSMetrics, stretches his legs while he is working. A growing number of workplaces are letting their employees use standing desks to alleviate back pain and improve blood

When they moved into their San Francisco office, the young workers of Kissmetrics, an Internet startup, didn't do much interior decorating. They left the walls bare and white. They chose not to install landline phones.

One thing was a must, however: standing desks.

Employees at the Web-analytics company crunch data, field e-mails and contact clients while standing in front of computers on stacked Ikea tables. Few sit behind a desk.

"For the first couple weeks, it was really hard. My knees hurt, my ankles hurt," Web developer Derek Collins, 31, said as he stood at his station, which overlooks Market Street from the company's 10th-floor office.

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"After 2 1/2, three weeks," he said, "it felt pretty good to stand."

Collins and his colleagues aren't standing alone. In a fast-growing number of workplaces across the United States, sitting is falling out of fashion, fueled by an increasing amount of medical research that shows that resting on your laurels for six or seven hours a day is unhealthy.

It heightens the risk of heart disease, neck and back problems, and diabetes, researchers say. What's more, off-the-clock exercise may not totally make up for it.

"The problem with sitting is that you're not doing something," said Wayne Smith, chief of physical medicine at Kaiser Permanente in San Jose, which provides regional spine care. "It's the inactivity that is the problem."

Moving away from sitting

Getting on your feet has big health benefits. Being seated less than three hours daily could boost life expectancy by two years, according to a July analysis of 167,000 adults that was led by the Pennington Biomedical Research Center in Louisiana.

Findings like these are propelling employers to help their workers by installing standing desks that bring monitors to eye level. The trend has exploded in popularity in recent years, particularly in health-conscious San Francisco.

Before Kissmetrics' office opened in June, employees worked on laptops in their homes and at cafes. Collins spent much of his time sitting on his couch, feet on the coffee table - and his lower back hurt.

"I don't notice it at all now," he said.

As comfortable as it is for most people, sitting is far from natural. The human body evolved to roam several miles a day in search of food.

"For most of us who are working in jobs where we have to sit at a computer, we're culturally mandated to sit," said Laura Putnam, a volunteer with the American Heart Association and founder of Motion Infusion, a San Francisco company that teaches organizations to be physically active. "But meanwhile, our bodies are physiologically pretty much the same as when we were hunters and gatherers."

Inactivity is known to weaken muscles and slow metabolism, which increases the risk of obesity. It restricts the body's ability to absorb and break down fatty acids. The more there are in an individual's bloodstream, the greater the risk of developing cardiovascular disease.

In addition, when muscles are not at work, insulin, the hormone that regulates the breakdown of blood sugars, circulates less. Blood sugar levels go up, which in turn increases the chance of contracting coronary artery disease, stroke and Type 2 diabetes.

Sitting hard on the spine

Sitting also places increased pressure on the shock absorbers of the spine. Many people experience spasms in the paralumbar muscles, which run along the spine, said Nancy Wiese, medical director of the Occupational Medicine Clinic at California Pacific Medical Center in San Francisco.

"When you're standing or when you're walking, you are shifting your weight and adjusting your posture, which is helpful for reducing muscular lower back pain," she said. When you sit, "you move around a bit, but you don't have much range of motion because your body is fixed in the chair."

Just how harmful is sitting?

A 2010 American Cancer Society study found that sitting more than six hours a day increased the death risk for women by 37 percent and men by 18 percent, compared with those who sat for less than three hours a day. The risk of dying remained virtually unchanged even after the researchers took into account the subjects' levels of physical activity.

Increased rate of death

The scientists drew their conclusion after spending 14 years tracking 123,216 men and women. About 19,230 of them died during that period, primarily from cardiovascular disease.

A March study led by scientists at the University of Sydney in Australia examined an even larger group - about 222,500 people ages 45 and older - for 11 years. Those who sat 11 or more hours daily had a 40 percent increased risk of dying in three years compared with those who sat for less than four hours a day.

Hitting the gym certainly helps, but scientists are mixed on just how much.

"Doing 150 minutes a week of moderate-intensity exercise probably doesn't wipe out all of the negative health consequences of sitting 12 to 16 hours a day," said exercise specialist William Haskell, professor emeritus of medicine at Stanford University School of Medicine. But, he added, it's much better "than if you sit all day and don't do anything else."

Collins, the Web developer at Kissmetrics, knows firsthand the pain of sitting. When he worked virtually, he'd roll out of bed, grab his MacBook Air, and head to his home office or a cafe.

"I literally can sit for eight hours a day," he said. "You get absorbed in what you're doing for hours and don't think about it except to go to the bathroom or get a drink of water."

Then, around age 27, pain in his tailbone peaked. He set reminders on his computer to walk around, but he ignored them. He went to the gym but thought it didn't help significantly.

"Sitting in a car became uncomfortable for more than 45 minutes or an hour," he said. "It was not fun at all."

That pain has disappeared now that he has a standing desk, plus a chair for backup use and a gel mat to cushion his feet. Three co-workers also built height-adjustable stations in the office, which can only fit half the company's two dozen workers at a time.

Standing desks' popularity

The desks have caught on among Bay Area tech companies, such as Google, Twitter, SoundCloud, Intuit and Yelp, where workers tend to be in their 20s and 30s, health conscious and driven to log long hours at the office.

"In the startup culture, what you do is sit at a computer and work all day," Collins said. "And you have a bunch of young people who say, 'I don't want to be unhealthy.' "

They aren't the only ones thinking it. Since Dan Sharkey of Ohio invented an adjustable-height desk and started selling it three years ago, sales have skyrocketed. This year, he expects to sell 6,000 units, twice the number sold in 2011.

"San Francisco is one of our biggest cities that buy our product," he said, citing its healthy population and high standard of living.

Nationwide, his clients include ESPN, Kaiser Permanente, NASA, Harvard Law School and Disney. "It's attorneys, it's grandmothers, it's students, it's guys building video games and everything in between, too," he said.

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